What makes a penis attractive? Not sure? Well, don't rely on your opinion to answer that question — science has the answer.

A new survey, published yesterday (July 23) in the Journal of Sexual Medicine, aimed to find out which qualities women consider most carefully when deciding whether a penis is attractive. Researchers from the University of Zurich in Switzerland first asked a group of 105 women, ranging in age from 16 to 45, to look at pictures of male genitalia and rate how "normal looking" they found each penis to be.

Next, the penis oglers answered questions about which penile qualities they considered most important when assessing the attractiveness of a man's package. Specifically, subjects were asked to rate the following attributes in order of importance: length of the penis, girth of the penis, position and shape of the meatus (the opening where certain fluids come out), shape of the glans (the rounded tip or head of the penis), appearance of the scrotum, appearance of the skin on the penis, appearance of pubic hair and the overall cosmetic appearance of the penis. [8 Wild Facts About the Penis]

Which of these qualities were most important to women? Perhaps not surprisingly, the position and shape of a man's meatus didn't matter much to the ladies. Almost as insignificant was the appearance of the scrotum, the researchers found. However, you might be surprised to learn that the third least important penis quality was length. That's right, fellas — it's not the size of the boat that matters.

So, what penile qualities do women care about? It turns out that ladies are looking for the total package, so to speak. Survey participants ranked the overall cosmetic appearance of a penis to be the most important quality they consider when assessing a man's genitals. But more specifically, they cared about hair — pubic hair, that is. The survey found that the appearance of body hair was the second-most important quality that women consider. Tied for third were girth and the appearance of penis skin, followed by the shape of the tip.

But besides answering a long-debated question, the penis assessment survey also had a scientific purpose: It was conducted to inform doctors who work with male patients with a condition known as hypospadias, in which the urethral opening of the penis (the aforementioned meatus) is located on the underside of the penis, instead of on the tip. Men who undergo surgery to correct this condition often report feeling that their penises look abnormal, even though health professionals tend to report that their patients' surgically altered penises look just fine.

As part of the survey, women were shown pictures of circumcised penises that were otherwise unaltered, as well as penises that had undergone surgery to correct hypospadias. The researchers found that, overall, women thought that the surgically altered penises looked just as normal as penises that hadn't undergone hypospadias surgery.

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